1) Field of the Invention
The invention relates to devices for separating a flowing medium comprising mixture into at least two fractions with differing mass density, and more particularly to plate separator devices a throughflow tank provided with such a plate separator device and a method for manufacturing a plate separator device.
2) Description of the Prior Art
The separation of fractions by means of sedimentation requires time and makes it necessary when processing larger volumes of medium mixture to make use of voluminous reservoirs, this being costly. Particularly, though not exclusively, in the separation of water and oil in the oil extraction and oil processing industry use is made here of throughflow tanks. These are so-called gravitational separators which make use of the difference in density between the fractions for separating (for instance oil particles dispersed in water). The separating efficiency of a gravitational separator is determined to a significant extent by the separating surface (F) and the throughput (Q). Particles with a rise speed greater than or equal to the surface load (Q/F) can be wholly separated. A gravitational separator is intended for the purpose of forming floating layers. The floating layer thus formed in the separator can subsequently be removed, for instance using a so-called skimmer or an overflow. In order to now increase the efficiency of a throughflow tank there already exist throughflow tanks in which use is made of one or more plate packs between which the fractions for separating flow. The advantage of applying a plate pack is that a more efficient separation is hereby obtained, by increasing the separating surface, than when a plate pack is absent. The result of the presence of a plate pack compared to the absence thereof is that the liquid need remain for a shorter period in the throughflow tank in order to nevertheless achieve a desired separating result. An additional advantage is accordingly that the throughflow tank can also be given a relatively compact form. However also other separations than fluid/fluid separation, like fluid/gas-separation or fluid/solid-separation, can be supported by the presence of a plate pack in the mixture flow to be separated.
The U.S. Pat. No. 5,904,850 discloses a settling device for a fluid containing liquid. The fluid is fed to a settling chamber wherein one or more caps are disposed with their longitudinal axis at an angle to the fluid level. The caps are positioned relative to each other by means of an essentially horizontally extending, V-shaped collecting cap. This V-shaped collecting cap extends through ridges of a row of successive mutually partially overlapping caps. Just below the V-shaped collecting cap passages are formed for the conduction of in particular gaseous fluid.
The drawback of the plate packs accelerating the separation of a medium comprising mixture is that the plate packs are relatively costly, bulky and the useful throughflow surface thereof is limited. The prior art plate packs are also labour-intensive to assemble.
The present invention has for its object to provide a device for separating a flowing medium comprising mixture which, while retaining the advantages of the prior art, is cheaper to manufacture and operate. The invention also has for its object to provide a throughflow tank provided with a plate separator device and to provide a method for manufacturing such a plate separator device.